As they campaigned successfully against property-rights Initiative 933 this fall, many opponents acknowledged the measure’s backers had a valid point — that growth-management rules can impose hardships on some landowners. They vowed to do something about it after the election.

Now some of them have unveiled more-detailed proposals. Several focus on expanding “transfer of development rights” (TDR) programs, already in place in some counties, that give owners of farm and forest land a way to make money off the development potential of their property without actually developing it.

“It would be neat if one day people could market their development rights the way they list their homes now,” said Michelle Connor, vice president of the Cascade Land Conservancy, a land-conservation group and one of the organizations backing the approach.

But supporters of I-933 say that, while there’s nothing wrong with bigger, better TDR programs, they don’t really deal with the fundamental problem the initiative tried to address.

“It doesn’t make the regulatory environment any easier,” said John Stuhlmiller of the Washington State Farm Bureau, I-933’s chief backer.

The initiative would have required governments to compensate property owners for many land-use restrictions. Supporters — who said they really wanted less regulation, not compensation — argued that government is using environmental rules to effectively seize private property for public use. Opponents said I-933 was overkill, that it would have touched off a development free-for-all and cost taxpayers billions.

Voters rejected I-933 by a wide margin. But its supporters said they would be back if their concerns weren’t addressed. And some opponents worried privately that, without a compromise, something like I-933 might pass someday.

In the proposed state budget she unveiled this month, Gov. Christine Gregoire, an I-933 foe, earmarked $100,000 for the William D. Ruckelshaus Center to convene interest groups for a dialogue on how to resolve conflicts between land-use regulations and property rights.

The center, a joint venture of the University of Washington and Washington State University, works to develop consensus on tough issues. Gregoire wants recommendations by October, aide Keith Phillips said.

Gregoire also requested $4 million to expand and provide seed money for local TDR programs, and $500,000 to establish a new state Office of Working Farms and Forests to work on similar efforts.

In a related development, the Cascade Agenda Coalition, a broad-based group led by the Cascade Land Conservancy, this month proposed that the Legislature establish a commission or task force to develop recommendations for making TDR programs work better.

The coalition, which includes environmentalists, business groups and developers, wants to protect 1.26 million acres, mostly farms and forests, in King, Snohomish, Pierce and Kittitas counties. TDR programs could help accomplish that without tax dollars, Connor said, and they also could provide a way to compensate rural landowners while still keeping their land rural.

Here’s how TDR programs work: Governments establish “sending sites” — lands they want to protect — and “receiving sites” — lands where development is encouraged. If they choose, owners of sending sites can then sell some or all of their legal right to develop their property to owners of receiving sites, who in turn can use that acquired right to develop their property more densely than zoning otherwise allows. Everything is voluntary.

In King County, which has the state’s best-developed program, the development rights to more than 90,000 acres of forest and farmland have been acquired. But all the transactions have been big one-shot deals put together with much government involvement.

Connor and Mark Sollitto, who manages the county’s program, say no broad marketplace for development rights has emerged yet. That’s in large part because cities have been reluctant to designate “receiving lands” for more intense development, they add.

“Everybody knows what lands we want to protect,” Connor said. “That’s not the problem.” Establishing incentives for cities to get more involved is key to making TDR programs more effective, she said.

Ken Miller of the Washington Farm Forestry Association, which represents smaller tree farmers, is part of the Cascade Agenda Coalition’s leadership team. Unlike most other members, he also supported I-933.

Miller applauds the coalition’s call for expanded TDR programs. “It could be a vehicle to keep a lot more rural land rural in perpetuity,” he said.

But that alone won’t satisfy I-933’s backers, Miller added. Most supported the initiative not because they wanted to develop their land, he said, but because they wanted relief from regulations that hinder them from using their property as they always have — and also sometimes force them to sell to developers.

Still, Miller said, the TDR proposal is evidence those who opposed I-933 may be paying more attention now to rural concerns: “To the extent it helps create a respect for the values rural folks contribute, that’s a good thing.”